What role for cardiac imaging in chronic coronary syndromes: review of the literature in light of the latest recommendations.

The 2019 ESC guidelines redefined stable coronary artery disease as chronic coronary syndrome (CCS), highlighting the dynamic nature of this disease. This condition is characterized by the gradual accumulation of atherosclerotic plaques in the epicardial coronary arteries. CCS can result in myocardial ischaemia due to supply-demand mismatch, often triggered by physical or emotional stress. The clinical course may be abruptly interrupted by plaque rupture or erosion, leading to acute coronary syndromes. Revolutionary advances in non-invasive imaging have transformed the chronic coronary syndrome diagnosis algorithm and management. Coronary computed tomography angiography provides detailed anatomical insights, identifying high-risk plaques with features like low attenuation and positive remodelling, as evidenced by SCOT-HEART, which reported reduced coronary events (HR: 0.59, P = 0.004). Stress echocardiography may detect ischaemia-induced wall motion abnormalities (sensitivity, 85-95%), while cardiovascular magnetic resonance is paramount in functional assessment, offering 81-86% sensitivity/specificity and detecting microvascular dysfunction via perfusion and late gadolinium enhancement. Nuclear imaging (SPECT/PET) enhances ischaemia detection, with PET's myocardial flow reserve improving prognostic accuracy (sensitivity 90%, specificity 88%). AI-driven innovations, such as CT-derived fractional flow reserve, automate plaque quantification and may reduce in the future unnecessary invasive angiographies by 19-25% (P = 0.01), while dynamic CT myocardial perfusion integrates anatomical and hemodynamic data, boosting diagnostic accuracy (87%). These advancements enable precise risk stratification and a personalized multimodal imaging approach, based on pre-test likelihood. It also increases the risk of unsustainable costs for society, repeated radiation exposure throughout a patient's life, and raises the question of actual limited benefits from revascularization in low-risk patients.